Balancing machine



. Oct-3,1939. v s. D LIVINGSTON 4,

BALANCING MACHINE Original Filed Feb. 27, 1930' 4 Sheets-Sheet 1 vINVENTOR Y 5' i 1 ATTORNEY as v 3: gnm am s. D. LlVlNGSTON 2,174,665

BALANCING MACHINE Gen 3, 1939.

Original Fild Feb. 27, 1930 4 Sheets-Sheet 2 INVENTOR d ,9

' 2- 7 ATTORNEY 5 3, 1939- v s. D. LIVINGS-TON 2, 174,665

BALANC ING MACHINE Original Filed Feb. 27, 950 4 Sfiegts-Sheet s INVENORTTO Get. 3,. 1939.

- BALANCING MACHINE br i mal Filed Feb. 27, 1930 4 sh et -sheet 4INVENTOR "t. 3 BY 5. ATTORNE s. D. LIVINGSTON 2,174,665 7 Patented Oct.3 1939 UNITED STATES PATENT OFFICE nsmome mourns Stanley 1). Livingston,Freeport, N. Y. Original application February 2'1, 1930, Serial Dividedand this'applicatlon May a 2. 1930, Serial No. 17.542

10 Claims. (01. 73-51) 'This invention relates to a machine forobtaining facts quantitatively determinative of the mass changenecessary' in a body to balance it while rotating.

Vibration in a machine is often caused by an unbalance in a rotortherein. This unbalance is due to unequilibrated centrifugal forcesgenerated in the rotor. The unbalanced centrifugal force may act onlyradially from the axisof rotation and substantially uniformly along thataxis. This condition is known as pure static un-= balance. latory motionofthe axis of rotation of the rotor to a new position parallel to itsinitial position.

' The unbalanced centrifugal forces may,act only at a rightangle to alongitudinal line drawn through the center'of mass of the body, and'beequal in opposite directions, that is, additive in eflect, on both sidesoi the center. This unbalance is known as pure dynamic unbalance. Puredynamic unbalance causes a pivoting of the axis of rotation upon an axisat a right angle thereto and positioned intermediate the ends of thebody.

A body rotatable upon a longitudinal axis is perhaps seldom encounteredwhich is in unbalance due to either pure static or pure dynamicunbalance. If the major efiect of the unbalance makes it appear asthough the body were statically unbalanced there is almost always aneffeet which makes it appear that the body is dynamically unbalanced.This probably generally arises from the fact that the mass causing whatappears to be a major effect of static unbalance does notlie exactly inthe transverse plane of the center of gravity or mass of the body. Whenthe major eflect is as though the body were dynamically unbalanced thereis also. generally an effect which makes it appear that the bodyisstatically unbalanced. This generally arises from the fact that theunbalanced centrifugal forces are not exactly equal and opposite on bothsides of the axis of rotation. This excess of mass on one sideof theaxis of rotation Pure static unbalance causes a transan axis at arightbalance has perhaps, unfortunately, become known as dynamic unbalance.

The word alpha as used in this specification,

-defines that component of unbalance in a body which tends to make thebody oscillate only about 6 an axis parallel to its axis of rotationwhen rotated about its longitudinal aids and so supported thatit mayoscillate as a whole, which oscillation is caused by a static unbalance.

-The word beta as used in this specification, v10 defines that componentof unbalance in a body which tends to make the body oscillate only aboutangle to its axis of rotation when rotated about its longitudinal axisandso supported. that it may oscillate as a whole, which 15 oscillationmay be caused either -by a static or a dynamic unbalance or by acombination of both.

Alpha. and beta components together define the tendency other than theactual axis of rotation.

Magnitudes corresponding to these two difi'er- 4 out tendenciescompletely define values of masses which must be added to the body tocompletely correct the tendencies.

Correction for unbalance requires subjection ofthe rotor to tests whichindicate the necessary I mass change in the rotor.

A principal object of applicant's invention is the provision of amachine by which the magnitude of the alpha component and the magnitudeof the beta component, may be ascertained by tests applied to the rotor,and then may be assigned, as a matter of computation, to'such positionson the rotor thatreither one ii actually ap-. 86

plied would not interfere with the inherent unbalance in the rotor due-to the other.

Another object of the invention is the provision of a machine-bywhichmagnitudes, one representing the alpha component the other the beta 40component, are obtained which are assigned, as

' a matter of computation, in such a way, that the computation of themagnitude of a single mass change as a resultant in a given plane isfacilitated,

A further object of the invention is to provide machine wherebymagnitudes are obtained whereby'the computation to assign the properposition of portions of the alpha magnitude and portions of betamagnitude is simplified.

A further obiect oi the invention is the provision of a'machine by whichthe general unbalance may be ascertained as two numerical quantities,

one of which may be considered alpha unbalance,

' that is, one component of unbalance; and the '55 of a body tov rotateabout an 20.

sion of a machine which preferably,

2 other may be considered as beta unbalance, that is, another componentof unbalance. A furtherv object of the invention or-mechanicalmanipulation to separate the efcorrections fects ofthe two kinds ofunbalance.

Other objects and advantages of the invention will appear as thedescription of a particular physical embodiment of machine proceeds, andthe novel features of the invention will beparticularly pointed out inthe appended claims.

The fundamental discovery, cants machine is that correction foralphanubalance may be so applied that it will have no efiect upon thebody, and correction for beta unbalance may be so applied that it willhave no effect upon the inherent beta unbalance of .the body to thuspractically and conveniently apply those they'must be distributed in atleast two transverse planes of the body, one on each side of thevertical plane. containing the axis by which the beta component ofunbalance is obtained. The correction for alpha unbalance must beapplied all on one side of the longitudinal axis of rotation anddistributed between the planes so as to generate centrifugal forceswhich collectively are equal and opposite to the inherent alphaunbalance and also so as to generate centrifugal forces balanced aboutthe beta axis.- The correction for beta unbalance must be applied onopposite radii from the longitudinal axis of rotation, partly on eachside of the vertical plane through the beta axis of a magnitude andposition, as regards the beta axis so as to produce a couple ofcentrifugal forces equal and opposite in effect to the .couple whichcauses the beta unbalance, and also so as to generate equal and oppositecentrifugal forces about the longitudinal axis of rotation. A

Applicant's invention is characterized by a principle which requiresrestrained oscillation of the rotor on each of two axes. One of the axesis parallel to the axis of rotation of the rotor. Oscillation on thisaxis ascertains the numerical quantity determinative of the alphaunbalance. The other oscillation axis is at a right angle to the firstand lies in a plane transverse to the longitudinal axis of rotation ofthe rotor. Oscillation on this last mentioned axis ascertains thenumerical quantity which is determinative of the beta unbalance of therotor.

It is to be observed that applicant has not narrowed the specificationof the axes, in that, the axis employed to obtain the alpha componenthas not been specified as necessarilylying in a vertical plane passingthrough the axis of rotation of the rotor, because such axis maycorrespond to and take all positions of the generatrix of a rightcylinder, the axis ofwhich coincides with the longitudinal axis ofrotation of the body; and the axis associated with the beta componenthas not been specified as necessarily lying in the-vertical planecutting the longitudinal axis of rotation and midway of the body,because it is evident, that this axis may lie anywhere in any verticalplane, transverse to the axis of rotation of the rotor between theplanes of correction.

Applicant's invention is further characterized by a principle whichrequires that the mass change ascertained from the numerical quantity,

determinative of the alpha unbalance shall be the basis of appliinherent beta unbalance-"of a nd in order distributed or assigned insuch manner that the resulting mass change in the rotor=will have noeffect upon the beta unbalance already existing therein. Thisrequirement necessitates applying the correction mass for the alphaunbalance all on one side of the longitudinal axis of rotation of thebody and in at least two planes, one on each side of the longitudinalcenter of the body.

It further requires that the amount on one side .of the axis by whichthe beta magnitude is ascertained shall be proportioned so that it willgenerate a moment about that axis equal to the moment generated by theamount on the other side and opposite in effect. This requirement ofequal moments generally necessitates a knowledge as to the distance ofeach correction plane from the axis, that is, the axis at a right angleto the longitudinal axis of rotation of the body, upon which the bodyoscillates when the numerical quantity determinative of the betaunbalance is being ascertained, although it is not to be understood bythis statement, that one must necessarily know as a numerical quantitythe linear distance of the correction plane from the axis, because bycalibrating a given machine employing a given rotor with known unbalancetherein a ratio may be ascertained which will equal the ratio of thelinear distances, if they were known.

It'is evident, then, that in order not to disturb beta unbalance whencorrecting for alpha unbalance, the correction mass applied by applicantmust be applied all on one side of the longitudinal axis of rotation andin a numerical amount equal to the numerical value of the alphaunbalshoe but in each correction plane inversely as the distance of thatcorrection plane from the axis upon which the body oscillates when thenumerical quantity determinative of beta unbalance is ascertained, andso as to generate equal moments about the beta axis.

Applicant's invention further requires that the correction applied forbeta unbalance shall be applied to the body in such a way that it willnot disturb alpha unbalance. This requires that the mass changenecessary for correction for beta unbalance shall be divided between atleast two planes one on each side of the beta axis. and the masses 180degrees apart as regards angular rotation in a'plane transverse to thelongitudinal axis of rotation, and positioned so that equal and oppositecentrifugal forces about the longitudinal axis of rotation aregenerated.

Correction for beta unbalance may be made in any two transverse planesof the rotor but if it is not made in the same planes in which thecorrection for alpha unbalance is made the absolute magnitude must bealtered so that it will generate the same moments, as it would havegenerated if it had been placed in those planes, about a given point,that is, the point of intersection of the longitudinal axis of rotationwith the transverse vertical plane passing through the axis upon whichthe oscillation took place for determining the beta correction, that is,in all cases it must generate a couple of centrifugal forces equal andopposite to the couple of centrifugal forces causing beta unbalance.

If correction for alpha unbalance is to be made in one pair of planesand correction for beta unbalance in another pair of planes the generalsum of zero turning moments, about the axis 76 by which: the betamagnitude is ascertained for the body; and the correction for betaunbalance will generate equal centrifugal directed from the longitudinalaxis of rotation and separated angularly 180 degrees in a planetransverse to the longitudinal axis of rotation.

. At the same time the correction for alpha. un-

balance will generate a resultant centrifugal force equal and oppositeto the unbalanced centrifugal force causing the alpha unbalance and thecorrection for the beta unbalance will generate centrifugal forcesforming forces equal and op posite, that is, forming an algebraic sum ofzero with the couple formed by the centrifugal forces causing betaunbalance. A further characteristic of applicant's invention is that anumerical quantity determinative of alpha unbalance may be indicated bya proper machine simultaneously with an indication of a numericalquantity determinative of the correc-" tion to be made for betaunbalance, that is, the oscillation from which the alpha. correction isascertained, ascertains the numerical quantity determinative of thecorrection for alpha unbalance, even it simultaneously anoscillation istaking place at an angle thereto which is determinative of thecorrection to be made beta unbalance and vice versa. No correctionwhatsoever needs to be made in the correction planes until after thevalues for all corrections to be made have been ascertained, although ifdesired, alpha correction may be made and the beta magnitudeascertained. Erom this it follows, that if the corrections have beenascertained for both alpha and for beta unbalance, it willfrequentlyoccur'that the correction for one kind of unbalance may be partially orfully cancelled by correction for the other; consequently bothcorrections may be efiected by a single addition or subtraction of massat one point in a particular plane and a single addition or subtractionof mass at a particular point in another plane.

\ As an embodiment of machine, applicant contemplates one in which theaxis of oscillation, from which the numerical quantity determinative ofthe beta unbalance is obtained-will be in a transverse plane between apair of planes in which correction for both alpha and beta unbalance isto be made. In case there are a plurality of pairs of correction planes,the position of the beta axis would'be between the planes considered aspairs, that is, as many planes on one side as on the other.

The preferred embodiment would have the axis in a median plane to eachpair. The ratiohereinbefore mentioned then becomes 1:1, so that afterthe numerical magnitude for correction for alpha unbalance has beenascertained it may be halved and one half applied in each correctionplane, where there is a single pair, and the numerical quantitydeterminative of correction for beta unbalance may behalved and ahalfplaced in each plane. If more than one pair of planes are used inwhich to makecorrection then the mass may be distributed equally in. anamount determined by dividing the total mass change into as many equalparts as there are correction planes and applying one part in eachplane. The correction for beta unbalance will be applied one half on oneside of the longitudinal axis of rotation and the other half on theother side-and could be distributed amongst those planes on one side ofthe median transverse plane in a ratio which would develop thereinmoments about the center axis used in determining the beta unforcesradiallyof the axis.

y 3 balance of the rotor equal numerically to the turning momentsgenerated by the distribution made in the correction planes on the otherside The simplest and most convenient and preferred embodiment ofamachine, where rotors of substantial length in proportion to theirdiameter are to be balanced, is to select two correction-planes,position the beta axis midway between those planes and apply correctionboth for alpha and betaunbalance in these two planes.

As the essential point of novelty in the machine of applicant'sinvention is directedparticularly to determining the numerical value ofcorrections to bemade, the transverse planes in which they are to bemade, the position of the correction mass in one plane as compared tothat in the other, and the position of the alpha correction as regardsthe beta in a given plane, further data is needed to enablethedetermination of a resultant single mass change a and its exactposition in each plane.

The further data needed is the position of the high point" and the angleof lag. These are bothwell known and understood facts and both maybeobtained by means which are old and well known. The high point and theangle of lag having been ascertained, the numerical quantities obtainedbythe oscillations caused by alpha unbalance and by beta unbalance arecombined therewith as a matterof computation or graphically. The resultof the method 0f treatment, whatever it may be, is that, in general, asingle mass change for each of the correction planes is ascertained andits exact position in these planes as regards angular rotations aboutthe longitudinal axis and radial distance therefrom. This change, whenmade, corrects unbalance in the rotor so that the rotor is then balancedboth statically and dynamically.

Applicant's machine, as lierein described, serves to determine numericalquantitative values which are usable together with other data such asthe position of the high point and the angle of lag of the' high pointby which to determine by means of computation -.or graphical-1y, as by awith means to permit oscillation about two axes,

one of which is parallel to the axis of rotation of the body and theother of which is perpendicular to the axis of rotation, the unbalanced-forcespresent in the body may be divided into two components, which aredesignated as thealpha component and.the beta component respectively,and the .beta component may be caused by a static unbalance or a dynamicundynamic unbalance. The alpha component is that part of the unbalanceas a whole which causes the body to oscillate only about the axisparallel to the axis of rotation, and the beta component'is that part ofthe unbalance as a whole which causes the body to oscillate only balanceor a combination of both static and I alpha of Fig. 3, viewed in theabout the axis perpendicular to the axis of rotation.

After the magnitudes of the alpha and beta components have beendetermined and the value.

equal to the mass change that is necessary at each end to producebalance regardless of the means used to determine the necessarycorrection for unbalance. Therefore, if desired, the

be combined vectorially and a single mass change made on each end thatwill compensate for both the alhpa and beta components.

. In describing the invention, reference will be had to a particularphysical embodiment of the machine and to the .drawings thereofaccompanying this specification, wherein like characters of referencedesignate like parts throughout the several views, and in which:

.Figure 1 is a front elevational view of a device embodying the mainprinciples of applicant's invention; Fig. 2 is a side elevational viewof the device as shown by right hand side as shown in Fig. 1; Fig. 3 isa sectional elevational view on the plane indicated by the line III-III,of Fig. 2, viewed in the direction of the arrows at theends of the line;Fig. 4 is atop plan view of the device as shown by Fig. 1; Fig. 5 is across-sectional elevational view on the planes indicated by the linesV-V at the ends of the lines; Fig. 6 is a cross-sectional elevationalview on the planes indicated by the lines VI-,-V I of Fig. 5, viewed inthe direction of the arrows at the ends oi the line; Fig. '7 is across-sectional view on the plane indicated by the line VII-VII of Fig.6, viewed in the direction of the arrows at the ends of the line; Fig. 8is an electric circuit and device included therein th the invention;Figs. 9 and ing the mathematical relations underlying theinventionpFigs. 11 and 12 are views .of the left hand end and the righthand end respectively of the body shown 'by- Fig. 10 aftercorrectionweights have been applied in the manner hereinafter described. I

. Broadly speaking, the particular physical embodiment selected byapplicant to illustrate the. principle of his invention, and illustratedin the drawings, includes'1., ,anelectric motor. designated generally byM, well shown in Figs; 3 and 5, for

' driving purposes; a supporting frame designated generally by F, andwell shown in Figs. 4 and 1,

The specific embodiment of for supporting a body, B, to be vbalancedwhile that body isibeing rotated by'the motor, M;

indicating means, I, well shown in Figs. 6 and '1, simultaneouslyoperative for exhibiting the extent of oscillation of frame F about eachof two axes when a body to be balanced is supported thereby andisrotated by the motor M.

applicant's invention shown in the drawings provides a suitable case,within which and withoutwhich various members going to make up thedevice are supported, so that the device is what might be calledself-contained.

Within the case i' andformed, preferably integral with a wall thereof,as: the front wall, are

lugs, as 2 and 2, one of which, 2, is shown in Fig.

5. and both of whichmre-shown in 6. Each and beta components for eachend: may

has a substantial right nut i8. The' lower end of the link I,

Fig. 1. viewed from the.

direction of the arrows 23, the shaft'2i is threaded a diagrammaticview'illustrating shown in Fig.

is designated 21, as

vbe balanced. The belt on the side of the motor remote from theconnection of the motor supporting arms, 5, a I

bracket I2 is attached in any suitable and appropriate manner as bywelding. This bracket angled extension it provided with an aperture ll.The aperture it receives a link i5 threaded throughout and provided witha flanged sleeve it on the upper portion thereof, as viewed in Fig. 5.Between the flange of the sleeve l5 and the extension i3 and surroundingthe sleeve and bearing upon thc flange and the extension i3 is acompression spring l1. Below the extension ltis a threaded w as shown inFig. 5, receives the end of a crank pin l9, which isalso well shown inFig. 3. Crank pin H, as best shown in .Fig. 3, is part of the crank armwhich is, mounted rigidly upon a shaft 2| extending through the side ofthe casing l and journaled in a bearing 22 formed, preferably, integralwith the casing l. The outer end of the shaft 2|, that is, the righthand end as viewed in Fig. 3, is provided with an outstanding arm 23,shown in Fig. 3, and also shownin side elevation in Fig. 2.

24 at the extremity remote from the shaft 2| ture 25 in the end throughwhich the shaft 2i is passed, correspondlngwith. a square portion of theshaft 2! adjacent-the end. Beyond the arm for the reception of a nut--28 which when screwed in place holds the handle member 23 firmlyinplace on the shaft 2i.

By the construction just hereinbefore described the handle pieceaffordsa means by which a manualoperation may be performed to raise orlower the arm 23, as shown crank pin cred. When link I! is raised, themotor M, as

5, is raised, that is, when handle This arm has-a handle piece in Fig.-2. thereby oscillating shaft 2i and with it the crank 20 and is wherebylink i! is raised and low- I piece 24 is raised, the motor M is raised.When handle piece 24 is lowered, link I! is lowered and the flangedsleeve i8 is drawn downwardly with link I5 compressing spring l'lagainst extension ii of the member I! attached to themotor M and soresiliently pressing the motor M downwardly.

Motor M has an armature, the'shaft of which best shown in Fig. 5. Thisshaft extends through the side of the casing i, and, within a'pulley andbeltguard 28 on the side ofthe casing i, bears a belt pulley 29, as

best shownin Fig. 3. This pulley 29 serves as a driving means fora.,belt 20, as shown in Fig. 3 and Fig. l, employed for driving the bodyB to 30, as best shown in Fig. 2, passes around. the pulley 2!, thenunder the body B and in contact therewith, then around a pulley 22 andback to pulley 29.

From the hereinbefore given description it will now be apparent that abody B to be balanced is in a position, as shown in Fig. 2, then if thehandle piece 24 is lowered the pulley 29 will contact firmly with thebelt 30 driving the same and" Fig. 2. Each of these rods is threaded oneach 7 causing a rotative eflort upon the body B or if handle piece 24is raised, as shown in Fig. 2, then the pulley 291 will not bearsufliclently tightly upon the belt to cause it to be driven andconsequently the body B will not have a rotaend for receiving nuts as35, 36, 31 and 38, as perhaps best shown in Fig. 4. Each rod has theinner raceway of a ball bearing belt pulley, guide or idler mountedthereon, as best shown in Fig. 2, in which the raceway on rbd 34 foridler 3| is designated 33 and the raceway on rod 33 for idler 32 isdesignated 40. As best shown in Fig. 4, a cross arm 4| is providedapertured on each end for the reception of the rods 33 and 34. In orderto position the cross arm 4| and hold it firmly in place and alsoposition and hold firmly in place the inner races of the ball bearareexactly like those placed about 33, are two short pieces 42 and 43between the inner race the nuts 36 and 38.

ings 39 and 4!), tubes are placed about the rods 33 and 34. The tubesplaced about rod 34-, which of the ball bearing member and 'two arms 44and .45 which are aperturedfto receive the rod 34; another tube 46between the arm 44 and the nut 35; and another tube4'l between the arm45 and the end of the member 4|. When nuts 35 and 31 are screwed tightlyin place on the ends of the rod 34, the arm 4|, the arms 44 and 45; andthe inner ball race '33 are all held firmly in place so 'as to be freefrom longitudinal movement upon the rod 34. By an identical constructionthe other end of the member 4| through which rod 33 passes and the innerball race 40 and arms 48 and 49 together with the tubes on the rod.33 I

are all held rigidly in place upon screwing on In order to support thebody 3 to bebalanced, stretchers '50 and 5|, best shown in Fig.4, areprovided. These stretchersextend from side to side of the frame restingupon the tubes surrounding the rods- 33 and 34 and are slidablelongitudinal of the tubesS Each is provided with a half round bearing 52as perhaps best shown in Fig. 2 for the reception of a shaft, as 53 ofthe body B to be balanced.

The frame F is supported by the arms #34, 45, 43 and 49. These arms as48 and 43 are really the two legs of a U-shaped member provided with aslot, as 54, as best shown in Fig. 1. Through this slot 54 extends two'leaf springs 55 and 56. Each spring is bent at a right angle so that aportion thereof, as 51 and 58, lies against the inside of the base ofthe U-shaped member. Above these turned over portions isa plate, as 59,pressed firmly against the turned over portions 51 and 58 and fastenedrigidly in any suitable or appropriate manner as by welding to the arms48 and 49. The lower ends of the spring members 55 and 56 extend downinto a slot as 30- in the end of one arm of a two armed lever 6| asshown in Figs. 1 and 2. Two armed lever 3| is rigidly mounted upon theshaft 62 mounted in ball bearings -63 and 64 supported by the case Asthe frame F is supported at a point approximating its longitudinalcenter on the symmetri cally formed two armed lever 6|, the frame isfree to oscillate in a vertical plane transverse to its length, that is,about the axis of the shaft 62,

greater or lesser oscillation of the plates '15 and of Fig. 4. TheframeF is also by reason of being that is, in the direction of the mm asand u' mounted upon the flat springs 55 and 56, free to in the directionof the arrows 31 and 68 of Fig. 3.-

It is, of course, understood that by the term "free ,to oscillatehereinbefore used is meant free to oscillate'against such restraint asis imposed.

If a body B to be balanced is supported by the stretchers as 50 and 5Iand the belt 33 is adjusted under the body as shown and then the belt iscaused to bedriven by the motor M the body B ,will rotate about thelongitudinal axis. If the body B is statically unbalanced then anoscillation of the frame F will be caused in the direction or the arrows55 and 66. If the body is dynamlcally unbalanced then an oscillation offrame F will be caused in the direction of the.

arrows 31 and sat .If both static and dynainic unbalance are present inthe body 3 then both oscillations will simultaneously take place.

The extent of oscillation caused by alpha unbalance is restrained by thefiat spring 69, well shown in Figs. 8 and 5.

Spring 83 is attached to shaft 62 in any suitable or appropriate manneras by cap screw 10. The ends of the spring 69 extend in two directionssubstantially at right angles to shaft 62, as best shown in Fig. 5, andthe ends thereof lie adjacentadjusting screws II and 12. By suitablyadjusting the screws 1| and 12, a desired tension may be placed upon thespring 53 so that an alpha unbalance in the body B will cause a shaft62.

The extent of oscillation caused by beta unbalance is restrained by fiatsprings 13 and 14,

shown in cross-section in Fig. 3, and in. side ele vation in Fig. 5 andin end elevation in Fig. 1. The upper spring 13 is clamped between the16 attachedrto arm 4| and the lower spring It bears upon the top of theright angled arm 71 attached, as by a 'cap screw 18, so as to rotatewith and about the longitudinal center line or axis of the shaft 62. Theouter ends of the springs as shown in Fig. 5 are held together byadjustable clamps as l9 and. These clamps can be approached nearertogether or be separated farther apart thereby increasing or decreasingthe reactive power of the springs 13 and I4.

If the frame F is caused to oscillate in the direction of the arrow 63,Fig. '3, that is, about an axis transverse to the longitudinal axis ofthe body B it is to a certain extent restrained by'the action of springs13 and I4 as spring 14 will bear upon the right angled arm l1 when theframe F moves in the direction of the arrow 38.

In order to exhibit the amount of oscillation caused by the alphaunbalance. and the amountcaused by the beta unbalance there have beenprovided an arm 8| extending out from shaft 62 and oscillatable withthat shaft and an arm 32 pivoted on a bracket 33" intermediate itslength and having one end positioned underneath and in contact withrod84. The rod 34 is provided with threads on its upper end and screws intoa cavity in the arm 4| and is adjustable by the knurled finger piece 85so that its lower end may be adjusted so as to lie exactly on thelongitudinal center line of the shaft 62 when the belt 30is not beingdriven.

' To the free ends of each of the levers 82' and would be a ratherdiflicult matter 1 trical contact may be balance in the body B pointers96 and the arm 94 ration of the contacts ."swingofthearmsasll 8| isattached a thread like member, as 86 and 81, respectively. Each of thethread like members, as 86 and 81, passes several times about a smallshaft, as 88 and 89, respectively, best shownin Fig. '1, and the end ofeach is attached to tension springs, as 99 and 9I, respectively. Theshafts 88 and 89 are each suitably mounted for oscillation, as by havingtheir ends formed conical and resting in conical depressions in memberssuch as 92 and 98. Each shaft, as 88 and 89, has arms, as 94 and 95,respectively, extending substantially at a is continued by a pointer, as96 and 91, respectively, forming a visible indicator.

The construction last above described is such that an oscillation ofshaft 62 causes an oscillation of arm 8I and a movement of thread 81which being wound about shaft-89 causes that shaft to rotate and the arm95 and pointer 91 carried thereby to be oscillated. In the same way avertical oscillation of the left hand end of the frame F, as viewed inFig. 3, causes the rod 84 to move downwardly and oscillate lever 92which by reason of being connected with thread 86 causes an oscillationof shaft 88 and the arm 94 and the pointer 96 connected therewith. Thepointers 96 and 91 may be viewed through an aperture in the front of thecasingas shown in Fig. 1 and by the extent of their movement so may thevalue of alpha and beta unto be balanced, be determined.

As the pointers 96 and 91 will be in a continual state of oscillationwhen the device is in use for ascertaining the unbalance of a body, itto determine alone the extreme swing 91. To the end of faciliaccuratelyby the eye. of the-pointers 96 and tating determining pointers 96 and91, applicant has provided pivoted sectors, as 98 and 99, adjacent eachof the pointers, as 96 and 91, and has graduated the edges of thesesectors 98 and- 99 adjacent the. 91, as indicated by Fig. 1 by I99 andIlll. On each of the sectors cooperating electrical contacts as I92 andW9 have been mounted. When a body 3 to be balanced is in motion and iscausing an oscillation of arm 99 or arm 96 or both, a button I94attached to sector 98 is grasped by the fingers and moved so as to bringthe end of contact M2 closer and closer to arm 94 until a point isreached where contacting with I92 causes a sepa- I92 and 898. This marksthe extreme oscillation of the arm 94 and pointer 91. In the same waythe button I is moved until the arm 95 just breaks the electric contactassociated therewith. 'The breaking of an'elecv indicated, ,as showninFig. 8, wherein a small lamp I96 is shown connected in circuit with thecontacts I92 and I-89 and a source of-potential I81. when the properadjustment of a sector as 98 is made the lamp will be extinguished uponeach oscillation of the pointer or arm 94 in the direction towards thecontact I92. This contact member I82, of course, must be made of suchsize that it'will not materially interfere with the free swing of thearm 94, that is, it must be extremely sensitive so asto require but verylittle appreciable force to operate it.-

After the exact adjustments of the sectors as 98 and 98 are obtained toindicate the extreme and 88 then after the from driving belt 89 bymotorMhasbeenfi-eed right angle thereto and each arm the extreme swingof the.

masses causing centrifugal a manipulation of the hand piece 24 thesectors as 98 and 99 will be in such position that the extreme swing ofthe pointers as 99 and 91 which occurred is indicated by the amount ofdisplacement of the sectors as 98 and 99 from an arbitrary zeroposition.

Applicant contemplates using a motor M of constant speed. He alsocontemplates so positioning the body B to be balanced that correctionplanes I98 and I99 will be positioned one on one side of the median lineI I0 and the other on the other side thereof and each at the samedistance from the median line and this median and provided with meansfor altering the mag nitude of the static and beta unbalance may bemounted upon the stretchers 69 and BI and then caused to rotate bydepressing the handle piece 84. Readings may then be taken of thedisplacement of the sectors 98 and 99 for a wide range of known changesin the magnitude of alpha and beta unbalance in me body of knowncharacteristics and fromthese/readings the device may be calibrated sothat upon placing a body asB in the device and rotating it and observingthe necessary displacement of sectors 98 and 99 the numerical magnitudeof both alpha and beta unbalance in the body B may be ascertained. By asingle mounting of the body or of the arrow's'61 and 88' furthercontemplates, in a determined as the body or rotor simultaneouslyoscillates 'with two degrees of freedom about two axes.

The mathematical relations which have to be observed when applyingcorrections determined by the use of the machine and the generalmathematical relations which subsist and which exemplify the principlesunderlying the invention are illustrated by the diagrams Figs. 9 and 10.Fig. 9 illustrates the general case. Fig. 10 illustrates the specialrangement of the specific embodiment shown in the drawings.

In Fig. 9, 3' indicates the unbalanced body; DA designates the betaaxis; LA designates the longitudinalaxis, and may also be considered torepresent the alpha axis. If the body B and numerical resultsdeterminative of both alpha and beta unbalance obtained, then aftercorrection the correction masses will bear proper relation to oneanother as centrifugal forces. The correction mass CF! considered as acentrifugal force added to thecorrection mass CF: considered as acentrifugal force will equal the original unbalanced alpha centrifugalforce, that is,

The moments ,generated by these centrifugal forces about the beta axiswill bear the following relation: CF1sX=CF:xY. The above equationsillustrate the disposition and relation of the forces which countercedalpha centrifugal force balance the unb is oscillatedair-1,00; a

but do not themselves'create an unbalanced beta force. t I e The massesdetermined by oscillation applied to body B to compensate beta unbalanceare CF; and m. These masses considered as centrifugal forces have arelation which may be expressed by a formula as follows:CF3Xa+CF4Xb=original beta couple unbalance. These masses considered ascentrifugal forces also bear the following relation: CFa-,= CF4. Theforegoing equations and mathematical relations not only illustrate howcorrection masses are to be applied but also illustrate the fundamentalrelations which must subsist, as hereinbefore pointed out, in order thata correction mass ance without generating a beta unbalance and how abeta unbalance correction may be applied without generating an'alphaunbalance.

In- Fig. 10 the subsist withthe preferred special formof the inventionas illustrated by the drawings is em ployed. When this special form isusedthe beta axis DA is positioned midway between the correction planesCP and CP', that is, :c=y=,a=b and R=R'.- Under'such conditionscalculations and corrections may be made on the basis of weight ratherthan centrifugal force; W1=Wz and Wa=W4. a

In the particular arrangement shown in the drawings the magnitude ormass change necessary to correct the body B for alpha unbalance would behalved and one half assigned to each correction plane as I08 and I09.The magnitude or mass change necessary to correct for beta unbalancewould also be halved and one half placed in the correction plane I08 andthe other half placed in the correction plane I09. When makingcorrection for alpha unbalance all of the mass changes would be made onone side of the longitudinal center line and in a line parallel thereto.When making correction for beta unbalance one portion any mass changemay be made to correct are two masses in each correction would be placedon one side-oi the longitudinal center line and the other portion on theother side of the longitudinal center line'and on the other side of thetransverse axis upon which oscillation takes place to determine theextent of beta unbalance and correction mass in'one plane would beangularly 180 degrees from the position of the correction mass in theother plane, that is, if the beta correction mass were placed in thecorrection plane I8, in the plane right hand corner of body B as shownin Fig. 10, then the other correction mass for beta unbalance would beplaced, in the plane of the paper, in correction plane I09 at the lowerleft hand corner of the body B as viewed in Fig. 10.

Applicants device does not determine what is technically known as highpoint" or angle of lag. It merely determines the numerical magnitudesnecessary to correct for unbalance. Before for unbalance the high pointand angle of lag determined. This may be done by well known and approvedmethods thoroughly understood by termined the numerical magnitudesascertained by applicant's device are then distributed in the twocorrection planes in accordance with the determined high point and angleof lag. As there plane, one for alpha and the other for beta unbalance,it is perfectly feasible before actually applying any correction mass bycomputation as vectorially, to ascertain a single resultant correctionmass for may be applied for alpha unbal-' mathematical relations whichof the paper at the upper must be with this resultant in each plane.

By applicants device a single positioning of a body to be balanced ismade and after thatpositioning a rotation thereof is caused from whichdata is secured sumcient to ascertain in connection with the high pointahd angle of lag the necessary mass changes in on thereof in order tobalance the body both statically and dynamically and the instrumentreadings by which. the magnitude is ascertained persist so that they maybe read at leisure, as the rotative displacement of are stationary atthe time of reading. In order to actually balance a body which is inunbalance it is necessary to determine the high spot, angle of lag, andmagnitude of the unbalance.

In order to determine'the high spot, the body is mounted in the frame Fjust as the body B is mounted. While the body is moving freely aboutboth the alpha and the beta axes, a scribe is placed I confusion withthe caused tolightly mark will be made beta unbalance.

alpha high spot and the scribe touch the shaft whereupon a indicative ofthe high point for In order to determine the angle of lag, it is to beremembered that the body is mounted resiliently, that is with a minimumdamping, consequently, the angle of the high spot behind the age ofchange in speed either above or below the critical or resonant speed.The resonance mentioned above is readily detected by the extreme ormaximum vibration which is evidenced when the body is rotated. This maybe and usually is observed by the unaided eye. The speed is generallyincreased until it is greater than the resonant speed and thenthedriving power is shut off and the body allowed to coast to a stop. Thegoing of the body through the critical or resonant speed is tude ofvibration.

The magnitude of unbalance is obtained by measuring the lineardisplacement 'of the rotating two bodies, both of which the body and theposireadily observable by the amplition may be accomplishedmathematically from static measurement of the mass of the system andelasticity of the springs or more practically by placing a body in themachine, making high spot and alpha and beta unbalance reading and thenknown test weights being applied at known points and the reduction invibration produced by the known weights noted. Since the restrainingsprings have a, straight line elastic characteristic the calibrationcurve is a straight line and there fore only two points are necessary todraw the curve.

If a body such as that shown by Fig. is to be balanced and thecorrection planes are the planes of the ends of the body, the body wouldbe placed in the machine as shown by Figs. 1 to 8 inclusive and rotatedand the alpha reading and the beta reading are both 10 cated by thepointers 96 and 91. The readings are taken above resonance therefore thelag angle is 180 degrees and the highspots are the light spots, theangular location of the high spots would be determined by a scriber ashereinbefore pointed out, the alpha high spot by a scrlber in ahorizontal plane and the beta high spot by the scriber in a verticalplane. Since the body was placed in the machine with the beta axismidway between the end planes of the body all of the data is nowobtained by which-to balance the body.

In Figs. 11 and ends of the body as shown by Fig. 10 but both ends areviewed from the same end. lnlFig. 11, iii designates the correctionweight of five units applied to the left hand of the body shown in Fig.ll), at the alpha high spot, or light spot. In Fig. 12, H3 designates acorrection weight of five units applied to the right hand end of thebody shown by Fig. 10 at the alpha high spot or light spot.

In Fig. 11, ill designates a beta correction weight the left hand end of.the

of five units applied to body as shown by Fig. or light spot.

The other weight of the beta couple is applied 180 degrees from theweight I It at the other end or right hand end of the body ill and isdesi nated M5.

10 at the beta high spot It will be noted that the alphacorrectionweights have been so located with respect to the beta axesthat the couple created by these weights about the beta axisiszero,therefore the beta component of unbalance in the body has notbeen disturbed by applying the correction of alpha unbalance. In thesame way, the correction for beta-unbalance has been divided betweenthecorrection planes to produce a balancing couple without introducingany change in the unbalance of the body as respects the alpha axis.Since the body has been balanced for both alpha and beta components andis suspended with two degrees of freedom, it will be in balance whenrotated in any type of suspension.

Although I have particularly described the principle of operationnevertheless, I desire to have it understood that the particularphysical embodiment selected is merely illustrative and does not exhaustthe pus--v sible physical embodiments of the idea of means underlying myinvention or the physical embodiments by which my invention may bepracticed.-

This application is a division of my copending units on the scaleas indi12 are shown two views of the and construction of a particular physicalembodiment of my invention,"

shaft mounted for oscillation;

. awaees application Serial No. 431,719,- filed February 2'7,

1. In a balancing machine, in combination: a

shaft mounted foroscillation; resilient means restraining oscillation ofthe shaft; a frame supported by the shaft; resilient means between theframe and the shaft allowing oscillation of the frame about an axis at aright angle to the axis of the shaft; a third resilient means uniformlrestraining the last mentioned oscillation of the frame in anyoscillated positionof the shaft; a member attached to the frame andterminating at the longitudinal center line of the shaft prolonged whenthe frame is at rest in uno'scilla'ted position; means actuated by saidlast named member for indicating the extent of oscillation of the frame;a member attached to the shaft;

- means actuated by said last named member for indicating the extent ofoscillation of the shaft; and means for supporting on the frame a bodyto be balanced and rotating it whereby oscillations of the shaft and theframe will be caused and the extent of such oscillations are usable incalculating the masschanges necessary to balance the body.

2. In an indicator for a balancing machine, in combination: a. firstpivoted pointer; a second pivoted pointer; means for pivoting eachpointer in-one direction by oscillations caused by the rotation of anunbalanced rotating body; means for returning each pointer to initialpositions; a pivoted sector adjacent each pointer, shiftable oversubstantially the arc of movement of the adjacent pointer; a set ofcooperating electrical contacts on each sector, each set having an armlying in the path of movement of a pointer when a sector is properlyadjusted; electrical circuits for each set including an electricallyenergizable device and a source of energy whereby when the polinters areoscillated and the. sectors are proper y erated toinfluence theelectrically energizable lation of the pointers is ascertained.

3. In a balancing machine, in combination: means for rotating a body tobe.balanced; a frame for supporting thebody to be balanced whileit isrotating; means allowing the frame to oscillate restrainedlysimultaneously on two axes one at a right angle to the other, one axisbeing between and at known distances from at least two correction planesof the body; means simultaneously acting for indicating the extent ofmovement on each axis whereby data usable in correcting the body forunbalance is obtained.-

4. In a balancing machine, in combination: a shaft mounted forrestrained oscillation; a frame supported by the shaft; means forsupporting a body to be balanced for rotation on the frame; means fordriving the body; means allowing the frame to oscillate restrainedlywith the oscillation of the shaft on an axis at aright angle to the axisof the shaft, said last mentioned axis positioned between and at knowndistances from at least two correction planes of the body; means forsimultaneously determining the extent of oscillation of the shaft andthe oscillation of the frame at a right angle to the axis thereof whenthe body is rotated whereby data usable in correcting the body forunbalance is obtained.

5. In a balancing machine, in combination: a

adjusted the cooperating contacts are op-' simultaneously I I a framesupported by the shaft; means for supporting and rotating a body to bebalanced on the frame; means connecting the shaft and the frame wherebythe frame may oscillate about an axis at a right angle to the axis tothe shaft, said last mentioned" axis being between and at knowndistances from at least two correction planes of the body; resilientmeans for restraining the said oscillation of the frame; means attachedto the shaft and oscillatable therewith for bearing against the saidresilient means whereby the said resilient means is tensioned uniformlyfor all positions of the said shaft.

6. In a balancing machine, in combination: a motor; means for rotating abody to be balanced driven by the motor; a frame for supporting the bodyto be balanced while it is rotating; means allowing the frame tooscillate restrainedly simultaneously on two axes one at a right angleto the other, one of said axes being between and at known distances fromat least two correction planes of the body; means simultaneously actingfor indicating the extent of movement on each axis whereby data usablein correcting the body for unbalance is obtained.

7 -7. In a balancing machine, in combination: a housing; orificed lugsattached to the housing;

. pins, one passing through an orifice of each lug;

supporting arms, each supporting arm formed with an orifice at one endand a plurality of spaced orificed lugs at the other end, eachsupporting arm being pivoted on one of the said pins; a motor providedwith lugs matching the lugs of the arms and orifices for fasteningthereto by screw-like'means and screw-like means for such attachment; abracket attached to the motor; a link resiliently attached to thebracket; a crank connected to the link; and means for operating thecrank whereby the motor is oscillated; a belt pulley driven by themotor; a belt driven by the belt pulley; a frame having two degrees offree-- dom and provided with means for supporting a body to be balanced;and means for-guiding the belt in contact with the body to be balancedwhereby the body to be balanced is rotated.

'8. In a balancingmachine, in combination:

; means for rotating a body to be balanced; a frame for supporting thebody to be balanced while it is rotating; means allowing the'frame tooscillate restrainedly simultaneously on two axes one at a right angleto the other, and one axis between and at known distances from at leasttwocorrect ion planes ,of the body; means simulta- 4 neously acting forindicating the extent of movement on eachaxis whereby data usable incorrecting the body for unbalance is obtained.

9. In a balancing machine, in combination: means for rotating a body tobe balanced; a frame for supporting the body to be balanced while it isrotating; means-allowing the frame to oscillate restrainedlysimultaneously on two axes, one at a right angle to the other. one ofsaid axes being between two arbitrary planes of the body within whichcorrection for unbalance is to bemade and at known distancestherefrom;and means simultaneously acting for indicating the extent of movement oneach axis whereby data usable in correcting the body for unbalanceis'obtained.

10. In a balancing machine, in combination: means for rotating a body tobe balanced; a frame for supporting the body to be balanced while it isrotated; means allowing the frame to oscillate restrainedlysimultaneously on two axes, one at a right angle to the other, one axisbeing between and at known distances from at least two correction planesof the body; means manually controllable for indicating the extent ofmovement on each axis whereby data useable in correcting the body'forunbalance is obtained.

STANLEY n. LIVINGSTON.

